Mirrorless open cavities enabled by boundary incompatibility between perfect electric conductor and perfect magnetic conductor parallel-plate waveguides
摘要
The most basic approach to confining electromagnetic waves is to place mirrors along their path, yet achieving confinement without conventional mirrors remains a major challenge. Here, we demonstrate theoretically and numerically an open-geometry cavity that enables electromagnetic field confinement without physical mirrors. This mirrorless confinement arises from a mode gap induced by incompatible boundary conditions at the interface between perfect electric conductor (PEC) and perfect magnetic conductor (PMC) parallel-plate waveguides. By employing a metallic-groove artificial magnetic conductor to emulate PMC behavior, we realize open PEC–PMC cavities that exhibit strong field localization and an enhanced magnetic-dipole Purcell factor. Waveguide-coupling simulations reveal a sharp transmission resonance with a quality factor of